This three-year project involves the use of newly devised, computer-based behavioral techniques in studies of the development of complex auditory perceptual skills in normal preschool and school-aged children. Little is known about the development of auditory skills, probably because young children are so difficult to test. The methods to be used in this project consist of rigorous psychophysical paradigms which have been embedded in a video game in order to hold a child's interest. Several initial studies demonstrate that these techniques can be used successfully to assess auditory skills in normal children as young as three years. The proposed research will build upon the initial work by evaluating a wider range of basic auditory abilities than originally considered, and by assessing complex auditory skills such as temporal and spectral pattern recognition. These latter abilities are thought to be essential for successful speech understanding. A series of experiments will specifically address questions about the extent to which children's auditory abilities or our assessments of them are influenced by memory and attention. These issues will be investigated by studying the effects of background noise and stimulus uncertainty on auditory discriminations. Previous results suggest that both noise and uncertainty have much greater effects on children's auditory performance than in that of adults. All the experiments will involve children from three to eight years of age who are in the sense that they are not enrolled in special schools, and whose hearing is judged to be normal on the basis of standard audiometric assessment.